Loading hoist



J. R.- MCGIFFERTHET Al. ,131,479

LOADING n'ors'r Sept. 27, 1938.

Filed July 11, 1936 3 Sheets-Sheet 1 amz 3& W

Sept. 27, "1938 .Filecl July '11, 1936 J. R. M GIFFERT ET AL LOADING HOIST 3 Sheets-Sheet .3

Sept. 27, 1938; J. RIMCGIFFERT ET AL 4 2,131,479

LOADING HOIST Filed July 11, 1936 3 Sheets-Sheet g 50' by the tractor engine.

Patented Sept. 27, 1938 UNITED STATES PATENT. OFFICE LOADING nors'r John a. McGifiert and on L. Be -by- Duluth,'

Minn, assignors to Clyde Iron- Works, Duluth, Minn a corporation of Minnesota Application .my 11-, 19:0. Serial No. t me lzclalms.

Our invention relates to an improvement in loading hoists of a type designed to be readily movable from one position to another and which is particularly designed for use in loading logs on trucks, sleighs, or other vehicles, and is adaptable for general hoisting and material handling.

steel erection, pile driving. and clam shell. and

bucket. work.

Loading devices due to their size weight are naturally difficult to move from one position to another. We have found that where loading devices have been mounted upon crawler units or the like, they are often top heavy and unstable and are unable to lift heavy loads at any great ll distance from the hoist.

It is a feature of our invention to provide a loader whichis readily portable and yet which is firmly supported during loading operation. This feature is accomplished by providing rigid 20 legs pivoted to the frame of the loader in such a manner that they may be raised out of operative ground engaging position during the movement of the loader from one position to another, and yet which may firmly support the loader duringas loading operation.

It is a feature of our invention to provide a loader mounted upon a tractor preferably of the crawler type provided withsupporting legs for one end of the frame which may be .operated in 80 unison into contact with the ground. The movement of the tractor toward the legs may act to pivot the same into upright position to rigidly support one end of the loader frame. The legs are of suillcient length to relieve the weight on 36 one end of the tractor. so that the loader is entirely supported by the rigid legs and the spring supported end of the tractor.

Our invention resides in providing a loader which is mounted upon a standard tractor and 40 which is balanced in such a manner that the center of gra'vityfof the device coincides with the center of gravity of the tractor itself. In

this manner,' the pitching of the,loader during,

movement thereof is to a large degree eliminated. t5 Itis a feature of our, invention to provide a loader comprising a frame mounted upon a tractor and extending beyond the ends'thereof and having at one end of the frame a live boom and a double drum hoist operated by power supplied frame is provided with a counter-weight tocountor-balance the weight of the hoisting equipment. The load is in this way counter-balanced during movement of the hoist. By providing the rigid 5s legs at the extreme end of the frame supporting equipment.

The other. end ofthe the hoisting equipment a heavy load may be lifted at the end of the boom and which is counterbalanced by the weight of the hoist and tractor as well as by the counter-weight.

These and other novel features and objects 5 of our invention will be clearly andfully set forth in the following specification and claims.

In the drawings forming a part of thisspeciflcation:

Figure 1 is a side elevation view of our loader 10 in loading position.

Figure 2 is a front elevation view of the same with the boom cut oil and the hoisting machinery omitted to show the detail of the construction of the front. 16

Figure 3 is an enlarged view of the front endof the hoist frame, disclosing the leg of the frame in lowered position.

Figure 4 isaview similartol'igure 3,showing the pivoted legs in raised position.

Figure 5 is a perspective view of one of the piv-' oted legs, disclosing the construction thereof.

a pair of spaced channels ll which are secured intermediate their ends to a tractor B. tachment of the channels II to the tractor B may vary with the type of tractor used and in the type, disclosed, bolts directly at I. to the "frame at one end of the tractor and is secured Q adjacent the other end by means of brackets I4. '40 The channels I. are connected by suitable cros members, suoh as It, and areprovided at one end with a counter-balance box it within which may be placed sumcient ballast of any desirable type to cause the center of gravity of the assembled loader to coincide with that of the tractor B alone. The ballast box I! is placed at the end.

' of the frame projecting-forwardly from the front.

ll of the tractor. A hoist C is mounted OllgthE frame to the rear of the tractor-B, as will be more clearly described in detail. Power ofoperation of the hoist is provided by means of the power take-oi! shaft sprocket i1.

.Attherearendsofthechannels llwepro-.

vide a vertical A-frame ll comprising a pair of la" The at--35 cross member l9 extending transversely across the channels l8 and projecting somewhat beyond the channels Ill. The channels forming the A- frame l8 are preferably secured to plates 28 which in turn are secured to the cross channel 9.

Centrally between the channels 18 and mounted upon the cross member 19, we provide a bevel connection 22'which is hingedly secured at 23 to a live boom 24. The boom 24 is constructed of special alloy steel of moderate weight and ample strength. The boom comprises a pair of ppositely disposed channels 25' connected by cross members 28 at spaced points.

Spaced plates 21 depend downwardly from each endof the cross channel 19 to accommodate legs 28 which are hingedly supported therebetween by means of a pivot pin 29. In the form illustrated, the legs 28 comprise a pair of channels 38 which are oppositely disposed and connected along one side of the covering plates 32. The inner plates 21Tadjacent each leg are provided with a flange 33 which projects into the body of the leg adjacent the inner channel 38 when the leg isin upright position as may be seen in Figure of the drawings.

This flange 33 acts to hold the leg with which it engages from side movement when the leg is in this upright position. A flange 34 on the inner plates 21 limits the upward movement of the legs 28 when the legs are drawn into inoperative position, as illustrated in Figure 4 of the drawings. The channels 38 are adjustabiy connected by bolts 35 or other suitable means to a pivot end 38 which is pivotally connected to the shoe 31. Each shoe 31 is provided with a bearing plate 38 having upturned ends 39. to which is secured a pair of upright channels 48. The pivot end 38 of each leg 28 is provided with a transversely extending pin 42 extending through 'slots 43 in the channels 40. Accordingly, the legs 28 are pivotally connected to the shoes 31 so that'the shoes '-is provided which will be later described toassist may maintain a substantially horizontal position by their own weight even when in inoperative position.

Each leg 28 is provided with a gear segment 44 attached along one side thereof which isengageable with a pinion 45 on a transversely extending shaft 46. As the pinions 48 are both secured for rotation with the shaft 48, it may be seen that the legs '28 pivot in unison to prevent one' leg from assuming a vertical position before th other due to uneven ground surface.

The legs 28 with the'shoes 31 are somewhat" longer than the normal distance between the frame and the surface of the ground. Accordcontact with the ground as shown in Figure 8 of the drawings. The tractor B is then driven rearwardly for a short distance, the shoes 31 engaging the ground and pivoting into the vertical position illustrated in Figures 1 and 3. A means tical position, the rear end 41 will be raised slightly from the' surface of the ground. In the n tractor B disclosed, the front end 18 thereof is" -channels secured at their lower extremities toa spring suspended, while the rear end is the rigidly supported end of the tractor, and accordingly the loader A is supported entirely by the legs 28 and by the spring suspended end of the tractor B. This fact enables the loader to beerected upon somewhat uneven ground without straining the frame work and provides the equivalent of a three-point mounting rather than a four-point support as would be found if the rigidly supported end of the tractor remained incontact with the surface of the ground.

The hoist C disclosed, is provided with two cable drums 48, each or either of which may be used separately or simultaneously. In normal operation, the boom 24 is connected to the top of the A-frame by a tie cable 49 so that the reach of the boom remains constant during the loading operation. The boom 24, however, may be raised above this position upon occasion bya cable operable upon one of the cable drums 48 and extending through a sheave 58 at the top of the A- frame and connected to the outer extremity of the boom 24.

The manner in which the various cables are driven is best illustrated in Figure 3 of the drawings. From the power take-off I1 of the tractor B, a chain 52 operates a sprocket 53 one shaft 54 upon which is mounted a pinion 55. The pinion 55' meshes with .a gear 58 on a shaft 51. The gear 58 engages the gear 58 on a shaft 59. A gear 80 on the shaft 51 engages a gear 82 on a shaft 83. One of the cable drums 48 is mounted upon the shaft 51, while the other is mounted also controlled bysuitable controls 84. A cable 88 is wound upon one friction drum 85, passes through a sheave 81 to a sheave 88 on the boom 24. The cable 88 passes over the sheave 88 through a pulley 89 mounted on the adjacent end of the cross channel l8 and is secured to the sheave bracket 18 of the sheave 88 on the boom 24. The other friction drum 85 is likewise provided with a cable 12 passing through a sheave 13 on the frame, through a sheave 14 on the boom, back through a pulley on the adjacent end of .the cross member l8, and is ended at the sheave bracket 18 on the boom 24. Movement of one of the drums 85 will act to pivot the boom toward the engaged friction drum 85while the cable will pay out from the opposite friction drum 85. In order to. prevent slack in the cables 88 and 12.

'we provide a cable 11 terminating on one drum 85 and passing through sheaves 18 and 19 with its other end secured to the opposite friction drum 85. This cable 11 causes the drums to move 1 uniformly and to pay out an amount of cable from one drum 85which is wound upon the other drum. Spring bumpers 80 are mounted on the cables 88 and 12 to limit the swinging of the boom ner plates 27. This construction comprises a cross channel 8| below and parallel to the channel I9. From the outer ends of the channel 88. channels 85 are secured slanting inwardly and upplate 81 is welded or otherwise attached between the cross channels to form a truss or girder reinforcement for the center of the cross channel I9 upon which the boom 28 is pivotally obstacles. Each bumper 89 comprises a cylinder 90 having a loop 92 thereon for connection with the loader frame, and a bearing end 98 slidably.

connected to the lower end thereof. A spring 88 is interposed between the cylinder 00 and the bearing end 93 thereon within the cylinder, and acts to cushion any longitudinal rocking of the loader frame.

From the foregoing description, the operation of our loader is believed readily understood. In moving from one position to another, the legs 28 are in raised position, and are held in this position by means of the load cable 85 on one of the cable drums 48, which is engaged In a loop 86 on each leg 28. Where the loader A is being used for loading logs or the like, a sling 81 is ordinarily used having two hooks connected to a connecting ring'on the cable 85. One of these hooks may be inserted through the loop 88 on each leg in drawing the legs 28 into inoperative position, shown in Figure 4.

When it is desired to operate the loader, the tractor is moved to the desired point, and the load cable 55 is'lowered, the shoes 81 contacting the surface of the ground. The cable 85 is removed 'from the loops 86, and the tractor 3 moved rearwardly until the legs are pivoted intov upright position. Pins 88 may then be inserted through the legs and into the inner plate 21 as shown in Figure 5, to hold the legs in upright position.

In some cases the surface of the ground upon which the loader is to be operated is smooth or slippery, and rearward movement of the tractor B when the shoes 81 are in partially erected 'position illustrated in Figure 8 merely slides these shoes over the surface of the ground. To avoid" trouble in such cases in properly erecting the legs,

we provide a sheave I on the shaft 48 having a short length of cable III secured thereto with a ring I02 on its free end. The load cable is carried over the sheave III on the cross channel 84 and attached to the ring I02. By exerting a pull on the load cable 85 as the tractor 13 moves rearwardly, the sheave I03 is rotated, turning the shaft 48 and the pinion l5, forcibly erecting the legs as the tractor moves.

The cables 85 and I04 from the two drums 88 may be used simultaneously or separately and individually as desired. As has been stated, one cable may be used for raising the boom 20 if desired. When used for raising a load, the cable passes over one of a pair of sheaves 50 at the top of the A-frame, over one of a pair of sheaves I05 at the base or pivoted end of the boom 28,

and through a sheave I08 at the free end of the boom. The other load line I04 may pass through the others of the pairs of sheaves 50, I05, I08, if desired. This line I04 may also be used as a drag line, or as a guy line by extending it through one of the pulleys 50 in the opposite direction from that usually used, and by anchoring the line to a fixed anchor I01 at a point in front of the I tractor B. 7

When it is desired to change the position of the loader, the setting up'procedure is reversed. The pins 98 are first removed, and the tractor B is then driven forwardly until the legs 28 assume the position illustrated in Figure 8 of the drawings. The load line 98 is then attached to the loops'88 of the legs, and the legs drawn upwardly into the position illustrated in Figure 4 of the drawings.

When the legs 28 are in supporting position, the loader rests entirely upon the legs 28 and upon the spring supported end of the tractor B. In tractors of the crawler type, one end of each tread is spring supported; and it is desired to have this end contact the ground so as to .compensate for uneven ground, and to prevent strain on the frame of the loader.

In accordance with the patent statutes, we have-described the principles of operation of 'our loading hoist; and while we have endeavored to set forth the best embodiment thereof, we desire to have it understood that this is only illustrative of a means of carrying out our invention, and that obvious changes may be made within the scope of the following claims without departing from the spirit of our invention.

We claim: 1

1. A tractor supported hoist in combination with a tractor comprising a frame secured to said tractor, a pair of supporting legs securedto one end of said frame, aligned pivots connecting said legs to said frame and means connecting said legs to pivot in unison.

2. A tractor supported hoist in combination with a tractor comprising a frame longitudinally secured to said tractor, ahoisting unit on said frame, legs on said'frame longitudinally spaced from said tractor, aligned pivots connecting said frame and legs, and means connecting said legs to operate said legs in unison.

'3. A tractor supported hoist in combination with a tractor comprising a frame longitudinally secured to said tractor, legs pivotally secured on transversely aligned pivots to said frame, bearing shoes pivotally mounted on said legs, and means connecting said legstopivot the same in unison.

4. Ahoisting device in combination with a'tractor including a frame secured to the tractor and extending beyond one end thereof, supporting means for said extended end of said framepivotally secured to said extended end and movable into vertical position, and means engageable with said supporting means to lock the same in vertical position, said locking means including a locking'pin, said supporting means being of sufficient length to take the weight off oneend of said tractor.

5.'A hoisting device in combination with a supporting vehicle having longitudinally spaced weight supporting points, including a frame extending beyond said weight supporting points, supporting means pivotally connected to said frame beyond said weight supporting points and movable into vertical position, means locking said supporting means in vertical position, said locking means including a locking pin said sup- 75 porting means being of sufficient length to raise said end of said frame to take the weight off one of said weight supporting points.

6. A hoisting device in combination with a supporting vehicle including a frame secured on said vehicle, a supporting means on said frame longitudinally pivotal into and out of engagement with the surface of the ground, and shoulder means on said frame engageable with said supporting means at a point spaced from the pivot thereof when said supporting means is in engagemeiit with the ground-to limit transverse movement in either direction of said supporting means.

7. A hoisting device in combination with a supporting vehicle'including a frame on said vehicle, a pair of supporting means on one end of said frame pivotally engageable with the ground, a pivotally supported shaft, means connecting said shaft and supporting means to rotate said shaft when said supporting means is pivoted, and means onsaid shaft for pivoting said supporting means in either direction.

8. A hoisting device in combination with a supporting vehicle including a frame extending substantially beyond the vehicle, and resilient bumper means depending from said frame engageable with the ground and normally spaced from the ground to mollify any pitching thereof.

9. A hoisting device in combination with a supporting vehicle including a frame extending beyond said vehicle, and bumper means swingably depending from said frame into normal spaced relation with the ground adapted to dampen any pitching of said vehicle by engagement with the ground, and to pass freely over obstructions.

10. In a loadinghoist, a tractor, a frame on said tractor extending substantially beyond the ends of said tractor, and a bumper means swing- -ably depending from said frame adjacent each bers extended, said spring permitting said mem-' bers to compress when said bumper strikes the ground.

12. In a loading hoist, a tractor, a frame thereupon, a pair of pivotally mounted legs on one end of said frame pivotally movable into engagement with'the ground, shoulder means on said frame limiting the pivotal movement of each of said legs, and flange means on said frame engageable with each said leg when said leg is in contact with said shoulder to prevent axial side movement of said legs with respect to said frame.

JOHN R. MCGIFFERT. OLA L. BERBY. 

